Even if you do start out the day with plenty of fuel, you may eventually feel that energy slipping away. You can be zipping along just fine, then—Boom!—you hit what sports enthusiasts call "the wall." How well you handle your energy budget will determine whether you break through the wall and move on to the rest of your day—or just bounce off and slog through the mental mud.

No matter how often you might wish otherwise, you are not a robot and can’t go non-stop. That's especially true of those of you who are desk-bound for most of the day. It's a simple fact that sitting at a desk for hours at a time can decrease your energy level. Occasional breaks are necessary for mental and physical health: you need to get up and stretch your legs, to get your heart pumping and your blood circulating.

However, too many rest periods can be detrimental to your productivity. If you don’t have enough endurance, you’ll be forced to break more frequently, and you won’t get anything done. Therefore, you need to strike a balance between taking too many breaks during the day and not breaking enough, because both practices can be equally harmful. To do that, you'll need to build up your endurance and learn to pace yourself, just like a long-distance runner or mountain climber would. Think of pacing as a form of sports training for high energy.

1. Stand instead of sit. You're not designed to sit for hours on end. Work regular physical movement into your work day, especially if most of your work is conducted at a desk. At the very least, stand up and stretch occasionally.
2. Give yourself a break. Failing to take breaks can affect your short-term energy and long-term health. Take a few minutes off from the grind occasionally so your body can restore your strength and energy.
3. Walk around on your breaks. Instead of drinking coffee and reading the paper while on break, walk around a bit. This lets your body process glucose better, giving you a burst of energy that'll kick in about the time you get back to work.
4. Try creative desk energy renewal strategies. Jobs requiring an intense focus can be intensely draining. Take an occasional break and renew yourself through meditation, deep breathing, prayer, stretching -- whatever works for you. For a free eBook on desk stretches, send an email to Stretches@TheProductivityPro.com.
5. Find an encouragement partner. If you're stuck with a boring task, find someone you can call up when you're temporarily burnt out. You can perform the same function for your partner; encouraging them can keep you on track, too.
6. Watch your posture. Don't slouch. Doing so uses up more energy than sitting up straight, and can also stress your musculature and skeleton. Getting a good, ergonomic chair can go a long way towards maintaining your proper energy level.
7. Pace yourself. Remember, you're not a machine; don't squander your energy early in the day, or you'll fade by mid-afternoon. Rest is as important as hard work for achieving anything of consequence in a decent amount of time.
8. Respect your biological cycles. No matter what you do, you'll go through energy cycles during the day. Circadian rhythms, sleep cycles, hormone cycles, and similar biological clocks can all conspire to rob you of energy. Instead of trying to work through the low cycles, take a few minutes off to revamp your energy level.

Hopefully you’ve learned ways to concentrate on a task, some techniques to bring you back to a state of alertness, and generally improve your endurance during the day. If your energy does crash, you know how to physically recharge your batteries and bring yourself back to a state of alertness. Your mind and body will thank you for the break, and reward you with renewed energy.